A new video released by the jihadi terror group, the Islamic State, depicts children, abducted and trained to kill by ISIS, executing 25 men identified as soldiers for the Syrian regime of Bashar al-Assad.

The massacre occurs in the historic amphitheater at Palmyra, an ancient Roman city cited as a UNESCO World Heritage Site that has recently been overrun by ISIS terrorists.

The video depicts children pulling the triggers against more than 25 men identified as Assad’s soldiers, egged on by a large crowd of men and boys forced to watched the ceremony. The men are lined up on their knees as they usually are in Islamic State execution videos.

The boys watching, reports note, appear younger than the boys pulling the trigger, who appear to be in their teens and can be thus believed to have completely or come close to completing terrorist camp training forced on boys living in Islamic State territories. The Islamic State has released multiple videos showing training camps for both boys and girls, in which the “caliphate cubs” are shown learning how to use automatic weapons and building explosives. The video is believed to have been released by an ISIS group close to the ravaged Syrian city of Homs.

The Daily Mail notes that experts have estimated that at least 500 children have been abducted by ISIS for use as child soldiers in recent weeks, particularly from the Iraqi provinces of Anbar and Diyala. The BBC notes that this particular video does not have many indications making it easy to place when it was filmed.

The Islamic State captured the ancient city of Palmyra in May, an area replete with priceless ruins and artifacts now in the line of fire. ISIS jihadists have become notorious for destroying such pre-Islamic artifacts, claiming that their existence constitutes “idolatry” to false ancient gods, and thus they must be destroyed before the eyes of Allah. While the group initially released a video promising that they would not destroy ruins in Palmyra that did not violate this “idolatry” provision, recent photos indicate that many of the ruins have been removed from the area, and the city itself has been filled with land mines. The amphitheater appears intact, perhaps due to its usefulness as an arena in which to dramatically stage executions.

Defying their promise, photos published by Islamic State supporters on social media this week show ancient statues being destroyed in Palmyra, all representing pre-Islamic gods and supernatural creatures. Of particular note is the destruction of the Lion of al-Lat, a 2000-year-old statue dedicated to an ancient Middle Eastern deity discovered in 1977.